Welfare Secretary Iain Duncan Smith rounded on the BBC today for seeking out “politically-motivated” people to attack his benefit cap policy.

The minister hit out in a live radio interview after he was confronted with the case of a London woman who said his reforms were costing her £98 a week. Rebecca, whose full name was not disclosed, said she could be forced to leave her neighbourhood.

Mr Duncan Smith insisted the benefits cap ­— which limits claimants to a maximum of around £500 a week — had succeeded in getting people on welfare to find jobs during trials in London boroughs. “I believe this to be right,” he said. “I believe we are already seeing people go back to work who were not going to go back until the cap.”

However, his claim was contested by councils, which say only four per cent of families subjected to the cap in one borough, Haringey found jobs afterwards. The row follows criticism by the official statistics body of the Government’s claims that 8,000 people found jobs after their benefits were capped.

Today’s interview on the BBC’s flagship Today programme on Radio 4 marked the beginning of a national roll-out of the cap. Veteran broadcaster John Humphrys asked if the minister was effectively telling people to move out of costly areas like London.

“No, we believe there is plenty of accommodation in London,” said Mr Duncan Smith. He added: “The great talk about thousands being made homeless has not come true.”

Mr Humphrys goaded him: “What you are doing is punishing people.” Sounding irritated, Mr Duncan Smith said people “working and paying their taxes” could not understand why some families got more from benefits.

Mr Humphrys butted in: “But that’s not the point I am putting to you.” Mr Duncan Smith hit out: “No, what you are doing, as always happens in the BBC, is seeking out lots of little cases from people who are politically motivated to say this is wrong.”

Under the benefits cap, couples and lone parents will not receive more than £26,000, an average income. Single people are capped at £350 a week. Claire Kobe, leader of Haringey, claimed that 740 families were severely disadvantaged from the cap during trials. Only 34 found jobs.

An Ipsos MORI poll found that only 11 per cent of the public think the benefits system is working effectively. Some 59 per cent said they wanted politicians to do more to cut Britain’s welfare bill. And 74 per cent backed the benefits cap. Charities criticised it. Matthew Reed, chief executive of the Children’s Society, branded it a “blunt instrument” and said children were seven times more likely to lose out.

Chin chin Dave: PM’s twitter gaffe

David Cameron was left red-faced today after an open message of support he thought he sent to his Pensions Secretary on Twitter was actually sent to a spoof account.

At around 8am the Prime Minister posted a message backing Iain Duncan Smith’s welfare reforms being rolled out today, but he sent it to the Twitter user @IDS-MP.

The account is an anonymous spoof which has posted comments such as: “I’ve always supported a Mansion Tax. Your Tax buys my Mansion. Chin chin!” and “a thrifty way to keep cool in this heatwave is to dab the ice from your champagne bucket onto your forehead”. In response to the Prime Minister’s comment, @IDS-UK tweeted: “Chin chin Dave. Round mine for a Pimms later?”

Mr Cameron was a latecomer to Twitter having previously said he was worried that “too many tweets might make a twat”.